The present invention relates to an apparatus for forming fibrous sheet material, and more particularly it relates to an apparatus for aerodynamically forming a fibrous sheet material, e.g. paper, cardboard, non-woven materials, and can be utilized in the pulp-and-paper, textile and construction material industries, in plants forming fibrous materials.
At present, there are known apparatus for aerodynamically forming a fibrous sheet material, including means for continuously and uniformly distributing fibres in a stream of an air-material mixture made up by the fibres and a gas having for its components air and particles or droplets of moisture, the means communicating with a forming chamber. The forming chamber includes walls and a perforated bottom in the form of an endless conveyor running over driven rolls. A device for sucking-in the gas from the air-material mixture, as the latter settles on the bottom of the forming chamber, underlies the conveyor (see U.S.S.R Pat. No. 222,299, Int. Cl. D 21 j 3/12). As the moving stream of the fibres in the air-material mixture contacts the walls of the forming chamber, the fibres become electrostatically charged, which results in their aggregation into flocks. The higher the speed of the motion of the fibres of the air-material mixture in the forming chamber, i.e. the higher the speed of formation of the fibrous material and the higher the productivity of the apparatus, the flocking action becomes correspondingly more pronounced. Consequently, the known apparatus fails to ensure a high degree of uniformity of the distribution of the fibres in the final sheet of the fibrous material, which effects the quality of the latter.